We can differentiate them on the basis of their mass numbers. Isotopes have same atomic number but different mass number.
Answer:
2.25g of NaF are needed to prepare the buffer of pH = 3.2
Explanation:
The mixture of a weak acid (HF) with its conjugate base (NaF), produce a buffer. To find the pH of a buffer we must use H-H equation:
pH = pKa + log [A-] / [HA]
<em>Where pH is the pH of the buffer that you want = 3.2, pKa is the pKa of HF = 3.17, and [] could be taken as the moles of A-, the conjugate base (NaF) and the weak acid, HA, (HF). </em>
The moles of HF are:
500mL = 0.500L * (0.100mol/L) = 0.0500 moles HF
Replacing:
3.2 = 3.17 + log [A-] / [0.0500moles]
0.03 = log [A-] / [0.0500moles]
1.017152 = [A-] / [0.0500moles]
[A-] = 0.0500mol * 1.017152
[A-] = 0.0536 moles NaF
The mass could be obtained using the molar mass of NaF (41.99g/mol):
0.0536 moles NaF * (41.99g/mol) =
<h3>2.25g of NaF are needed to prepare the buffer of pH = 3.2</h3>
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trust me plz i am good at chemistry
Krypton has 36 protons and electrons and 48 neutrons.
Answer:
Explanation:
no. of moles of butane = 5.87g / 58.124 = 0.1009mol
since O2 is excess, limiting reagent is butane
from the equation, 2 moles of butane will reacted to produce water = 10 moles
therefore, 0.1009 moles of butane produced water = (0.1009 x 5) = 0.5050 moles
Weight of H2O formed = 0.5050 x 18.015 = 9.10 grams
